Oil cooler



NW 26 1949 w. R. RAMsAUR TAL., 2,222,721

OIL COOLER Filed April 15', 193e 4 sheets-sheet 1 NOV. 26, 1940. w, R, RAMSAUR E17-AL 2,222,721

' V OIL COOLER Filed-April 13, 1956v I sheets-sheet 2 Nov. 26, 1940. O w. R. RAMsAUR Erm.

OIL COOLER Flled April 15, 1936 4 'Sheets-Sheet 3 Nov. 26, 1940. w. R. RAMSAUR Err/M V IL cooLEn Filed April 1:5, 1936.

4 Sheets-Sheet 4 Patented Nev. 26, 1940 f PATENT OFFICE om cooLEn Walter B. and Gharles J. OBrlen, Lockport, N. Y., assignors toGeneral Motors Corpos ration, Detroit, Mich., a corporation of Dela- Ware Application April 13, 1936, Serial No.- 73,988

Claims. (Cl. 257-245) This invention relates to heat exchangers and, particularly, to internall combustion engine lubricant temperature regulators which are hereafter Y referred to as oil coolers. 5 One of the objects of the invention is to provide a heat exchanger of high elciency which is capable of withstanding the temperatures and pressures to which it will be subjected when in-4 stalled in an internal combustion engine pressure lubricating system and'yet is of -simpleland inexpensive construetion and offers little resistance to the passage of lubricant through it. For a better understanding of the nature and objects of this invention, reference is made to the following specification and the accompanying drawings.

In the accompanying drawings: Figure l shows an oil cooler in which our inventon is embodied installed on an internal com- Abustion engine.

Figure 2 is an enlarged view of the oil cooler shown in Figure 1 with parts broken away.

Figure 3 is a view in' which the core of the oil cooler shown in the preceding figures is shown in elevation and the case thereof in section on the line 3-3 of Figure 2.

Figure 4 is an enlarged fragmentary view, mainly in section on the line 3-3 of Figure 2.'

Figure 5 is an exploded view of elements em- 80 ployed in the manufacture of the core of the oil cooler shown in the preceding-figures.

Figure 6 is a view ofthe elements of the core of' the oil cooler shown in the preceding figures assembled in a brazing fixture.

85 Figure '7 is a perspective view of one of the spacers which constitute parts of the brazing fixture shown in Figure 6.

Figure 8 is a view similar to Figure 2 of another oil cooler.

40 Figure 9 is a view in which the core of the oil cooler shown in Figure 8 is 'shown in elevation and the case thereof in section on the line 9-9 of Figure 8. l

' Figure 10 is a phantom view of a tube of the 46 oil cooler shown in Figures 1 to 4.

in which thecore is enclosed. The case consists of a sheet metal body I2 and a cast metal cover I3 to which the body is secured by screws I4. In opposite ends of the body I2, there are provided water inlet and outlet openings 3| and 32. In' 5 the cover I 3,- there are provided lubricant inlet and outlet openings 33 and 34. The core consists of a base I5 and a number of at tubes I6 which are preferably made of cupro-nickel and is disposed between the water inlet and outlet openl0 ings in the body and connected to the lubricant inlet and outlet openings in the cover of the case. The base-I5 consists of a plate of' metal, preferably iron, through which extend a pairof openings' 28 and in which there are secured three 16 studs 29.

vEach of the tubes I6 consists of a generally rectangular tray-like male element I1 and a similar female element I8 whose rim I9 snugly embraces and is metallically bonded to the rim 20 m of the male element. Within each tube, there are disposed two corrugated plates 2i which are preferably made of steel and are arranged end to end lengthwise of the tube with their corrugations extending lengthwise of the tube. The corruga- 86 tions in the plates 2I are approximately rectangular in formand their crests are metallically bonded alternately to the maleelement and to the female element of the tube. In each side of each corrugation, there are provided a series of $0 openings 22 separated by webs 23 so arranged that the openings in one side of each corrugation register with the webs in the other side thereof crosswise of the plate. Between the two plates 2I in eachtube I6, there is located a baille 24 which 35 consists of a thin strip of metal, preferably steel, whose edges are metallically bonded, respectively, to the male and female elements of the tube. The length of the bafile- 24 is considerably less than the width of the tube and its ends are spaced 40 equidistantly from the edges of the tube.

'Ihrough the male and female elements of each tube, except the outermost, and the corrugated plates 2| at about the centers of the latter, there extend openings which are encircled by outwardly projecting flanges 25 and 26 on the male and female elements. Corresponding openings are formed in `the male element of the outermost tube and in the corrugated plates in it but the female element of the outermost tube is left imperforate and reinforced opposite the openings in the male element and the corrugated plates by discs 21 of the same material l as the element metallically bonded to it. v

'Ihe innermost tube I6 is metallically bonded to 55 the base I5 with each of the flanges 25 on its male element projecting into one of the openings 28 in the base. Over each of the flanges 25 on the male element ofl each tube I6 (except the innermost) and over one of the flanges 26 on the female element ofthe tube immediately between it and the base vIt is sleeved a short length of tubing 30 which is made of the same material as the tubes and metallicslly bonded to both.

The core II is secured by the studs 29 and nuts 35 to the cover I3 of the case with one of the openings 28 in the base I5 in registration with each of the oil inlet and outlet openings and tit in the cover.

In manufacturing the core of the oil cooler shown in Figures 1 to 4 and 10, the elements of each tube It are formed and assembled in the manner described and illustrated with a sheet a t of copper foil about 0.002" thick interposed between the corrugated plates 2l and the baille 20 and the male element and a sheet b of copper foil about 0.0042" thick on .which there is formed a rim c` interposed between the corrugated plates thick is impaled on each of the iianges 25 and.

28 on the male and female elements of the tube and one of the short lengths of tubing 30 sleeved over each of the flanges 20 and seated on the washer d which is impaled on it.

After a number of the tube assemblies described in the next preceding paragraph have been made up', one of the"outermost" tube assemblies is seated .upside down on a suitable base plate A of stainless steel or other non-brazing heat-resisting metal. Then a pair of spacer plates B of the same material as the base plate are seated on top of the tube assembly with each of thesemi-circular notches C partly encircling one of the short lengths 'of tubing 30 and the notched edges of the plates abutting each other. After this, an inner" tubeassembly is seated on top of the spacer plates B with each,

of the flanges 26 on its female element projecting into one of theshort lengths of tubing 30 which are impaled on the anges 25 on the male element of the tube on which the spacer' plates are seated. The two operations last described are repeated until an assembly of `the desired number of tubes has been produced. Then a core base I5 is seated on the uppermost tube of the assembly with one of the openings 28 in the base encircling each of theilanges 25 on the male element of the tube and a sheet f of copper foil about 0.002" thickin which there are provided openings g corresponding to the openings in the base and openings h through which the studs 28 may be inserted interposed between the male element of the tube and the base. After this, a top plate D of the same material as the base plate A and spacer plates B is seated on top of the core base with the studs 29 on the latter extending through'openings in the former.

The core assembly in the fixture A--B-D is then transferred to a suitable furnace and heated in an atmosphere of hydrogen and other nonoxidizing gases until the sheets and washers of copper foil have fused and metallically bonded the several elements of the core. The tongues 36 on the extremities of the baiile 24 which extend into corrugations in the plates 2| prevent shifting of the baille prior to the time it is metallically bonded to the male and female ele, ments of the tube within which it is disposed. The top plate Dand the spacer plates B hold the elements of the `core assembly firmly together and the spacer plates prevent the tubes being distorted by the weight of the top plate and -the spacer plates above them during the brazing operation.

After the sheets and washers of copper foil have fused and metallically bonded the several elements oi the core, the core assembly is removed from the furnace and allowed to cool in the fixture A-B-D. After the core assembly has cooled, the top plate D is removed from it and the spacer platesB are withdrawn from between the tubes I6. The core is then ready for use. Y

As indicated in Figure 1, the oil cooler I shown in Figures 2, 3, 4 and l0 was designed for installation on an internal combustion engined? with one of the openings 3i` and 32 in the body of the case connected to the discharge side of the engine cooling water pump 08 and the other to the engine water jacket inlet pipe 39 and with one of the openings 33 and 34 in the cover of the case connected to the discharge side of the engine lubricant pump 40 and the other to a pipe 4I which leads to bearings of the engine. When the oil cooler is so installed and the engine is operating. the pump lill forces lubricant through one of the passages 33 and 3l in the cover I3 into what may be called the oil inlet duct of the core, thence in parallel through the several tubes I8 to what may be called the oil outlet duct of the core, and thence through the other oi. the passages 33 and 34 into the pipe 4i which leads to bearings of the engine. The terms oil inlet duct and oil outlet duct used in the next preceding sentence, oi.' course, designate, respectively, the passage which extends from the first and the passage which extends from the last mentioned passage in the cover I3 through the base I5 of the core, the "inner" tubes I6 and the short lengths oi' tubing 30 into the "outermost tube I6. In passing from the pump 58 into the pipe 39, the engine cooling water, of course. passes through the case of the oil coole` I0 and around and between the tubes I and extracts heat from or gives up heat to the oil within the core of the oil cooler.

The corrugated plates 2l, of course, prevent distortion of the tubes Il by the pressure of the oil within the tubes. They also serve as fins, and, consequently, expedite, transfer oi' heat between the water and the oil. They, furthermore.

eiect constant subdivision and reunion of the streams of oil flowing through'the tubes I 5 and cause the stresmlets oi' oil to follow tortuous courses and, consequently, raise the emciency of the o'il cooler. The efllciency oi the oil cooler is further increased by the baille 2l which, as Figure 10 indicates, causes the oil to travel cir- ,cuitously' instead of .directly from the oil inlet ductto the oil outlet duct. r

It is also to be noted that oil coolers of the type described, are much less likely to be ruptured by the strains imposed on them while they are in use than oil .coolers of the water tube type with soldered joints which have been used.

The use of oil tubes instead of water .tubes reduces the likelihood of' rupture as' a result of freezing of water within the cooler became 'it Afacilitates drainage of water from the cooler and eliminates connement of the water in spacesv with small dimensions. The use of copper instead of solder to bond the severeal elements of the oil cooler'together increases the mechanical strength of the joints and renders them less subject to deterioration by the heat to which they are subjected while the'cooler is in use.

The oil coolers shown in Figures 8', 9 and 11,

l2, 13 and y14 are' generally similar in construction and operation to and maybe made by the same general method as the oil cooler shown in Figures 1-4 and 10. Consequently, in describing these oil coolers, we yshall in general conne ourselves to pointing out wherein they differ from one of those previously described.

, Except inthat the cover 40 of the case is of sheet instead of cast metal and is secured to the body 4| by bolts and nuts 42 instead of screws and the core is of somewhat diierent construction, the oil cooler shown in Figures'8, 9 and 11 does notv differ materially from thatshown in Figures 1-4 and 10. The core of the oil cooler shown in Figures 8, 9 and 11 diilers from that shown in Figures 1-4 and 10 in two respects. One is thatl each tube 43 contains only a single corrugated plate 44 and the corrugations in this plate extend crosswise instead of lengthwise of the tube and the baille 24 is, of course, omitted.

The other difference is that insteadV of a base, such as I5, for the core, there are'provided two nipples 45 which are connected, respectively, to the oil inlet duct and the oil outlet duct of the core and secured bynuts 46 in openings in the cover 40. y f

The oil cooler shown in Figure 12 diiers materially from that shown in Figures 8, 9 and 11 only in that one of the ducts 50 which extends through the tubes 5| and 52 ls closed at-both ends and the other -55 is open at both ends and closed between the groups of tubes 5I and 52 by an imperforate disc 54. To each vend of the duct 55, there is connected a nipple 53 of which discharge side of the llubricant pump and the f other tothe pipe which leads to bearings of the engine. The lubricant discharged from the pump, of course, iiows in parallel through the tubes 5I (or 52) from the inlet section of the duct 55 to the duct 50 and, thence, in parallel through the tubes 52 (or 5l) into the outlet section of the duct 55. The oil cooler shown in Figure 13 differs materially Vfrom that shown in Figures 8, 9 and 11 only in that both of the' .ducts 50- which extend through the tubes 6l are located near one end of the, tubes, that there are in each tube two corrugated plates 62 w -ich are disposed endv to end crosswise of the tube and thatbetweenthe -strain on the flanges.

corrugated plates in each tube'there is interposed a baille 63 which extends from the end of the vtube near whichthe ducts 60 are located to a point near but at a distance from the opposite end of the tube. The baille 63, of course, causes the oil which enters each tube 6I through the inlet duct 50 to follow the eircuitous path indicated by the arrowsin order to reachthe out' let duct 3l).v

'Ihe oil cooler shown in Figure 14 differs materially from that shown in Figures 8, 9 and 11 only in that the oil inlet andl outlet ducts 10 are located fartherv from the'end's of the tubes 1I, that there are in each' tube two corrugated plates 'l2 which are disposed end to end crosswise of the 'tubes and that between the corrugated plate ineach tube there is interposed a baille-13 which extends 'rom near -one end tov near the' opposite end of the tube around one side of the oil 'inlet vduct 10 and the other side causes the oil which enters each tube from the oil inlet duct 10 to follow the circuitous path indicated bythe arrows to reach the oil outlet duct 10.

vWe claim: f l v 1, In a heat exchanger, a at tube, a pair of corrugated sheets disposed endY to endV between the side walls ofthe tube, and a baille interposed between' the adjacent ends of the corrugated sheets.

2. In a heat exchanger, a case which includes a body and cover, a core which includes a at tube disposed within the body, the tube Vhaving inlet and outlet openings in one of vits side walls and a flat mounting plate in which there are. provided inlet and outlet openings bonded as a unit to the mentioned side wall -of the tube inlet and outletl openings -which register, respectively, with the inlet and outlet openings in the plate and being separately/'secured to the plate and the body.

- 4 3. In a heat exchanger, cooperating vplates spaced apart to define afluid'passage, la pair of manifold uidvdistributor sheets disposed end to end in the uid passage between the specified plates, and a bale interposed between the adjacent ends of the sheets.

4. In a heat exchanger, av ilat tube, a pair of i corrugated sheets disposed end to end between the side walls' of the tube, and a baille interposed between the adjacent ends 'of the corrugated sheets with an angularly disposed end projecting into one of the corrugations. v

5. In a heat exchanger, a `pair of tubes, an orice encircled by a flange in a wall of one of the tubes, an oriilce encircled by a ilange in a wall of another of the tubes, and a tubular element which is closed between its ends telescoped around the mentioned flanges and connected to both tubes to space the tubes apart and relieve WALTER a. RAMSAUR. CHARLES J. o'nami. 

